LAKE FOREST, CA - AUGUST 16: (L-R) Presumptive Republican Presidential candidate U.S. Sen. John McCain (R-AZ), pastor Rick Warren and Presumptive Democratic Presidential candidate U.S. Sen. Barack Obama (D-IL) greet each other before the start of the Civil Forum on the Presidency at the Saddleback Church August 16, 2008 in Lake Forest, California. Obama and McCain participated in a town hall style meeting moderated by the Saddleback Church pastor Rick Warren. (Photo by Justin Sullivan/Getty Images)

Orange County After months of mudslinging, sniping and presidential campaign ad attacks, Democrat Barack Obama and Republican John McCain talked up civility, values and character Saturday, while outlining their stark differences on issues like abortion and stem cell research with one of America's most influential evangelical leaders.

The two candidates appeared side by side at the powerhouse Saddleback Church with its founder and spiritual leader, the Rev. Rick Warren, in a forum on presidential campaign issues that was noteworthy for its utter lack of negative attacks.

Both the Illinois senator and the Arizona senator were greeted with standing ovations, and they greeted each other warmly on stage, shaking hands and embracing as they appeared alongside Warren for their individual discussions on issues at the 23,000-member church.

Obama declined an invitation from McCain to participate in a town hall meeting at the church, but the two-hour event often provided illuminating contrasts as the candidate's tackled questions ranging from their most gut-wrenching life's challenge to their beliefs on America's role in the world.

"They clearly drew a bright line separating themselves on some issues," said political analyst Sherry Bebitch Jeffe, "but what was distinct here was they did it without smashing each other."

McCain, who has town hall forums from New Hampshire to California, appeared to treat the forum more as a campaign event, often reprising his well-worn jokes and stump speech segments. But he used humor often to the delight of the audience, and connected well with the crowd when he told several stories that underscored his own celebrated history as a POW.

But Obama also showed strengths: He appeared more thoughtful and comfortable discussing faith and domestic issues, exploring with relish the issues and moral dilemmas with Warren.

On the volatile issue of abortion, for example, Obama told Warren - who decried what he said were 40 million abortions since Roe vs. Wade - that "if you believe that life begins at conception and you are consistent on that belief, then I can't argue with you on that ... but there are ways that we can work together to reduce unwanted pregnancies."

"I am pro-choice. I believe in Roe v. Wade. ... not because I am pro-abortion ... but because, ultimately, I don't think women make these decisions casually," he said.

But Obama- in an answer that Republican partisans immediately pounced upon - sidestepped a question from the pastor who asked him to define at what point a human being gets human rights.

"Whether you're looking at it from a theological perspective or a scientific perspective, answering that question with specificity is above my pay grade," he said.

McCain, by contrast, did not hesitate on the question, saying to loud applause that human rights begin "at the moment of conception."

While Obama sidestepped a question on abortion, McCain sidestepped a question on who he defined as rich. At first, he joked and said that anything more than $5 million in income, but later he said "it doesn't matter" what he thinks on the issue, because "I don't want to raise anybody's taxes."

Illuminating differences

One question, in particular, illuminated the differences in life experience and outlook between the two candidates.

Asked first what was the most gut-wrenching decision he's ever had to make, Obama said it was that he "agonized" over his opposition to the Iraq war. He said that while he was "firmly convinced" there were no weapons of mass destruction in Iraq at the start of the war, it was also clear that Saddam Hussein "was a really bad person" who wanted to do the United States great harm. "You do everything you can to get that decision right," Obama said. "All those questions surrounding the war have been very difficult for me."

But McCain immediately aimed to underscore his experiences as a prisoner of war for six years during the Vietnam War - citing his decision in a prison camp in North Vietnam to reject an early release because he was the son of a high-ranking officer. "It took a lot of prayer," he said, and it ensured he would spend three more years in the camp, though he said he didn't regret it.

Defining marriage

The two candidates agreed that marriage is defined as the union of a man and a woman. But Obama said he opposed constitutional amendments to define it as such, and has called efforts like California's Proposition 8, which is slated to appear on the November ballot, divisive and discriminatory. McCain said he believed such matters should be left up to states, and expressed his support for Prop. 8.

The invitation to the Saddleback Civil Forum on the Presidency was initiated by Warren, 54, the founder of the Orange County institution and best-selling author of "The Purpose-Driven Life," who been described as "the most influential evangelical in America."

Warren, who questioned both candidates, surveyed churchgoers, pastors and experts to come up with identical questions for the candidates which he said were intended to avoid "gotcha" questions and shed light on the candidates' values and vision regarding leadership and America's role in the world.

A coin toss determined that Obama would sit with Warren for the first of the one-hour discussions on topics including stewardship, leadership and world view.

Invitation-only event

The Saddleback forum took place before a live invitation-only audience of 2,200 church members and another 2,000 who watched on television in a variety of locations on the 120-acres Saddleback campus.

The event also reached a live cable TV audience of millions who watched Obama and McCain tackle the issues, but it did not take place without protest. Independent party candidate Bob Barr mounted an unsuccessful legal challenge to be included in the presidential campaign event, and Atheists United protested that the church was an inappropriate forum for such a candidate's forum.

With just over a week until Democrats begin their national nominating convention in Denver - and two weeks until the Republicans convene in Minneapolis - the forum at one of the nation's most high-profile mega-churches provided a new and fresh lens on the two major party candidates, who have yet to meet in a formal debate.

It demanded that Obama and McCain connect personally with the charismatic pastor who is a powerful, well-known philanthropist and motivational speaker, as well with as his critical audience - churchgoing voters - while sharpening their performances and messages in an unscripted setting.

But that involved challenges for both the Republican and the Democrat: McCain is widely considered to be more skilled in town hall settings and extemporaneous discussions of issues - and he has repeated challenged Obama to join him in such forums. Obama is viewed as the more gifted and inspiring orator, who has the benefit of youthful appeal on stage. But his campaign - to the concern and puzzlement of many Democrats - has so far resisted McCain's efforts to appear with him at town hall events.

The Saddleback Forum

The Saddleback Church in Lake Forest (Orange County), was the site of the first joint appearance by Sens. Barack Obama and John McCain as major party candidates in the campaign on Saturday. Here are some facts about the 22,000 member mega-church, and its influential pastor, Rick Warren, who interviewed the Republican and the Democratic candidates on Saturday:

-- Founded in 1980 with one family, the church now has 100,000 names on its e-mail list, a 120-acre campus, and 300 community ministries, including those specializing in helping prisoners, CEOs, children with Down syndrome, addicts, single parents and people with HIV/AIDS.

-- Warren, the church's San Jose-born founder and pastor, has been listed as one of America's 25 best leaders, among "The World's 100 Most Powerful," and has been called America's most influential pastor. He has his own Web site at www.rickwarrennews.com.

-- Warren's book, "The Purpose Driven Life" is touted as the "best-selling hardback in American history." It has sold 40 million copies in this country, according to Publisher's Weekly. A best-seller for three years, it is published in 91 languages.

-- According to the Saddleback Church, "the Warrens give away 90 percent of their income through three charities - Acts of Mercy, which serves people with AIDS; Equipping Leaders, which trains leaders in developing countries, and the Global P.E.A.C.E. fund, which fights poverty, disease, corruption and illiteracy using local congregations."

How McCain, Obama fielded questions from mega-church pastor

Presidential candidates Barack Obama and John McCain expressed some major differences answering the same questions at the Saddleback Church Civil Forum Saturday. Among them:

What is America's greatest moral failure?

Obama: "America's greatest moral failure in my lifetime has been that we still don't abide by that basic precept in Matthew, that 'whatever you do for the least of my brothers, you do for me'."

McCain: "I think that America's greatest moral failure has been, throughout our existence, perhaps we have not devoted ourselves to causes greater than our self-interest."

At what point does a baby get human rights?

Obama: "Whether you are looking at it from a theological perspective or a scientific perspective, answering that question with specificity, you know, is above my pay grade. ... I am pro-choice. I believe in Roe v. Wade, and come to that conclusion not because I'm pro-abortion, but because ultimately I don't think women make these decisions casually."

McCain: "At the moment of conception. I have a 25-year pro-life record in the Congress, in the Senate, and as president of the United States, I will be a pro-life president. And this presidency will have pro-life policies."

Define "rich."

Obama: "If you are making $150,000 or less as a family, you're middle class. ... I would argue if you're making more than $250,000, then you're in the top 3 or 4 percent in this country, you're doing well. Under the approach I'm taking, if you're making $150,000 or less, you will see a tax cut."

McCain: "I don't want to take any money from the rich. I want everybody to get rich. I don't believe in class warfare or redistribution of the wealth. ... I don't want to raise anybody's taxes."

What is the most significant position you held 10 years ago that you no longer hold?